It is common practice to use material dispensing cartridges for dispensing various semi-fluid materials such as caulking compounds, sealing compounds, adhesives and the like. Such material dispensing cartridges include a relative rigid tubular body for receiving a quantity of the material to be dispensed, a tapered plastic dispensing tip at one end of the body and a movable closure plug at the other end which can be advanced through the body by the plunger on a cartridge dispensing gun, to force material from the body through the dispensing tip after it has been opened. Different materials and different applications require the use of material beads of different size and, when opening the dispensing tip, it is necessary to cut off the tapered tip at a location therealong in which the cross-sectional flow area corresponds to the desired size of the bead. The size and appearance of the bead is important to many applications, and it is necessary to not only cut off the tip at the proper location to give the desired size of bead, but to also form a clean cut free of burrs or feathered edges.
At present, it is the common practice to use a knife, razor or other sharp cutting tool to cut off the tip at a location that is gauged by the eye of the worker. Visual gauging of the point of cutting of the tapered dispensing tip is not precise and frequently results in variations in the size of the dispensed bead not only by different workers, but even when the same worker cuts the dispensing tip on successive cartridges. This variation in the size of the beads dispensed not only adversely affects the appearance of the job but also causes waste of material if the bead is oversize and may result in faulty sealing or adhesion if the bead is undersize. Further, the use of a knife or other sharp cutting tool to open the cartridges is a somewhat tedious operation. It is necessary to open or unsheath the knife or other sharp cutting tool, place the tip on a cutting surface, cut the tip and thereafter reclose or resheath the knife. In addition, cartridges commonly have a rupturable seal at the inner end of the dispensing tip, and it is necessary to use some elongated instrument other than the knife or cutter to rupture this seal. This necessitates either carrying another elongated tool or instrument or searching around for something such as a stick or wire which can be inserted through the cut-off dispensing tip to rupture the seal at the inner end of the tip.